describe('MismatchTree', function () {
  describe('#add', function () {
    describe('When the path is empty', function () {
      it('flags the root node as mismatched', function () {
        var tree = new jasmineUnderTest.MismatchTree();
        tree.add(new jasmineUnderTest.ObjectPath([]));
        expect(tree.isMismatch).toBe(true);
      });
    });

    describe('When the path is not empty', function () {
      it('flags the node as mismatched', function () {
        var tree = new jasmineUnderTest.MismatchTree();

        tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']));

        expect(tree.child('a').child('b').isMismatch).toBe(true);
      });

      it('does not flag ancestors as mismatched', function () {
        var tree = new jasmineUnderTest.MismatchTree();

        tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']));

        expect(tree.isMismatch).toBe(false);
        expect(tree.child('a').isMismatch).toBe(false);
      });
    });

    it('stores the formatter on only the target node', function () {
      var tree = new jasmineUnderTest.MismatchTree();

      tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']), formatter);

      expect(tree.formatter).toBeFalsy();
      expect(tree.child('a').formatter).toBeFalsy();
      expect(tree.child('a').child('b').formatter).toBe(formatter);
    });

    it('stores the path to the node', function () {
      var tree = new jasmineUnderTest.MismatchTree();

      tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']), formatter);

      expect(tree.child('a').child('b').path.components).toEqual(['a', 'b']);
    });
  });

  describe('#traverse', function () {
    it('calls the callback for all nodes that are or contain mismatches', function () {
      var tree = new jasmineUnderTest.MismatchTree();
      tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']), formatter);
      tree.add(new jasmineUnderTest.ObjectPath(['c']));
      var visit = jasmine.createSpy('visit').and.returnValue(true);

      tree.traverse(visit);

      expect(visit).toHaveBeenCalledWith(
        new jasmineUnderTest.ObjectPath([]), false, undefined
      );
      expect(visit).toHaveBeenCalledWith(
        new jasmineUnderTest.ObjectPath(['a']), false, undefined
      );
      expect(visit).toHaveBeenCalledWith(
        new jasmineUnderTest.ObjectPath(['a', 'b']), true, formatter
      );
      expect(visit).toHaveBeenCalledWith(
        new jasmineUnderTest.ObjectPath(['c']), true, undefined
      );
    });

    it('does not call the callback if there are no mismatches', function () {
      var tree = new jasmineUnderTest.MismatchTree();
      var visit = jasmine.createSpy('visit');

      tree.traverse(visit);

      expect(visit).not.toHaveBeenCalled();
    });

    it('visits parents before children', function () {
      var tree = new jasmineUnderTest.MismatchTree();
      tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']));
      var visited = [];

      tree.traverse(function (path) {
        visited.push(path);
        return true;
      });

      expect(visited).toEqual([
        new jasmineUnderTest.ObjectPath([]),
        new jasmineUnderTest.ObjectPath(['a']),
        new jasmineUnderTest.ObjectPath(['a', 'b'])
      ]);
    });

    it('visits children in the order they were recorded', function() {
      var tree = new jasmineUnderTest.MismatchTree();
      tree.add(new jasmineUnderTest.ObjectPath(['length']));
      tree.add(new jasmineUnderTest.ObjectPath([1]));
      var visited = [];

      tree.traverse(function (path) {
        visited.push(path);
        return true;
      });

      expect(visited).toEqual([
        new jasmineUnderTest.ObjectPath([]),
        new jasmineUnderTest.ObjectPath(['length']),
        new jasmineUnderTest.ObjectPath([1])
      ]);
    });

    it('does not visit children if the callback returns falsy', function() {
      var tree = new jasmineUnderTest.MismatchTree();
      tree.add(new jasmineUnderTest.ObjectPath(['a', 'b']));
      var visited = [];

      tree.traverse(function (path) {
        visited.push(path);
        return path.depth() === 0;
      });

      expect(visited).toEqual([
        new jasmineUnderTest.ObjectPath([]),
        new jasmineUnderTest.ObjectPath(['a'])
      ]);
    });
  });

  function formatter() {
  }

});
